The farming of animals, particularly commercially important animals such as cattle typically involves the administration of active agents such as vaccines or pesticides. It is frequently difficult and costly to deliver active agents to animals as this requires herding and containing the animals for that purpose.
A number of prior art treatment systems require delivery of an active agent by piercing the skin or tissue. Although these devices can effectively deliver the desired treatment, often the animal is exposed to the potential of post-treatment infections at the site of delivery. An additional problem with many of the prior art methods is that it can be difficult to determine or monitor which animal has been treated.
Known methods for remotely delivering agents to animals or humans can involve providing of aerosols in close proximity to the animal or person to be treated from a projectile that does not penetrate the skin or tissue. The use of aerosols cannot deliver a defined dosage of an active agent.
WO 2008/0522631 in the name of Smartvet Pty Ltd describes a remote treatment delivery system comprising a dosage projectile containing an active agent and a transdermal carrier. Typically the projectile will split or rupture on contact with an animal and the contents of the projectile, which may include a marker, will be transferred to the animal while the projectile shell falls away. In some cases, depending on the nature of the marker and the colour of the animal it can be difficult to determine which animals have been treated, particularly if the animals are viewed from a distance. In addition, the marker is contained within the projectile and is in solution with the active agent this restricts the choice and amount of marker to those that do not unduly reduce the efficacy of the active agent.
The present inventor has developed a dosage projectile which is configured to fragment on impact with an animal and leave at least some of these fragments of the shell on the skin or fur of the animal to produce a visible mark on the animal at the site of impact.